This invention relates to permanent magnet rotor assemblies, and more particularly, to rotor assemblies having a hub with rectangularly shaped tongues and wedge-shaped permanent magnets.
In the art, methods have been developed to join the non-magnetic hub to the magnetic pole pieces in a rotor assembly. One such method is the hot isostatic pressure (HIP) bonding process which is performed under extreme pressure (circa 18,000 p.s.i.a.) and at elevated temperatures (circa 2200.degree. F.). Another method used to join the nonmagnetic and magnetic rotor materials together is furnace brazing, which is also performed at elevated temperatures (circa 1860.degree. F.).
The elevated temperatures of either the HIP bonding or the brazing techniques reduce the strength of the two dissimilar metals, which is very undesirable in a high speed rotor where the strength of the rotor's components are of great importance.